Stenciling material.



0. F. GREEN.

STENGILING MATERIAL.

APPLIOATION FILED NOV.13, 1913.

Patented Feb. 9, 1915.

INVENTOR WITNESSES: v y W A TTORIVEYS 'EIEEES EDERIGK GREEN, F HORNCHURCH, ENGLAND, ASSIGNOB TO A. E. DIUK sa nn'omme nnmt.

heretofore commonly used, with respect to means for increasin the durability of such sheets in service. omposite stencil-sheets heretofore employed are usually made up of a protecting tissue, a waxed or otherwise treated sheet of porous paper and a relatively stifi and hard backing In these, it has been common to provide the backingsheet with a line of perforations a short,

distance from the forward edge of the sheet and along which line the major part of the backing-sheet may be torn after the sheet has been positioned upon the drum of the duplicator, so as to permit the ink to be passed therethrough. l[ have found that the severing of the backing-sheet by means of this line of perforations leaves a rough or sawtooth edge to that portion of theblank which is a permanent part of the composite stencil-sheet, and that under the influence of th pressure-roller this is pressed so firmly and sofrequently against the stencil-sheet as eventually to weaken the sheet at the point of contact. I, therefore, provide the composite stencil-sheet of this invention with a separate interleaving sheet of such length as to extend beyond the line of perforations along which the backingsheet is to be severed and therefore to interpose a cushion between the severed forward portion of the backing-sheet and the stencilsheet lying'next adjacent thereto.

In the drawings, Figure 1 is a plan view of the drum of a duplicator, illustrating the button-bar commonly used for coaction with the forward edge of the stencil-sheet; Fig. 2 is a'central cross-section thereof; Fig. 3 is an inverted plan View of the forward por-' tion of a composite stencil-sheet embodying this invention; and Fig.4 is a central longitudinal section thereof. 7

Referring to these drawings, it will be seen that the duplicator-drum is provided with a button-bar A, provided with suitably Specification of Letters Patent.

Application filed November 13, 1913. Serial No. 800,893.

a sufficient distance from the the present invention is to OF CHICAGO, ILLINOIS, A. CORPORATION OF ILLINOIS.

Patented Feb. d, t

spaced buttons or studs (1, a, for coaction with the stencil-sheet. The bar A is spaced eriphery of the drum to permit the stenc' -sheet to be passed between the button-bar and drum and the buttons or studs (1 extend through thebutton-barl and into the drum, so as to permit them to coact in mannerhereinafter stated with the forward edge of the stencilsheet.

The stencil-sheet as here shown is of the composite variety and comprises the protecting tissue B, the stencil proper C and the backing-sheet D. The protecting tissue is desirable when a stencil-sheet provided with a waxlike coating is employed, which is capable of being removed by the impact of the type. It may be dispensed with when employing stencil-sheets such as are now in common use, provided with a coating ofcoagulated protein. The backing-sheet l) is provided adjacent to its forward edge with a line of perforations 03. At its extreme forward edge, 1 preferably secure thereto a reinforcing sheet (2 of such width as to extend over the backing-sheet to a point rearward of the line of perforations (i. As will be seen, therefore, when the major portion of the backing-sheet D is severed along the'line of perforations d, the reinforcing sheet (1 will overlie the roughened edge of the'forward portion of the backing-sheet, so as to interpose a cushion between such roughened edge and the stencil-sheet C which immediately overlies it.

The stencil-sheet C, and preferably the protecting tissue B, are secured, preferably by adhesives, to the reinforcing sheet, as shown, or if desired directly to the backingsheet, either at its extreme forward edge or at a point intermediate of the same and the line of perforations d.

The extreme forward edge of the composite stencil-sheet here described is prefer ably provided with a series of openings cor- 1 responding in number and spacing to the ably of such size as to snugly receive the buttons or studs a, and, communicating with such notches, recesses e, the open forward ends of which are preferably of somewhat greater width than the diameter of said buttons or studs.

' In order to secure'the stencil-sheet in position upon the drum of the duplicator, it is necessary only to place the forward edge of the stencil-sheet adjacent to the button-bar and between the same and the surface of the duplicator-drum, and then press the said sheet forward until the buttons or studs a enter the recesses e to the full extent of such recesses. Then a lateral movement will bring the buttons or studs a into the notches e, whereupon a rearward movement of the stencil-sheet will bring said buttons or studs into coaction with the forward portions of the notches e, permitting suflicient pressure to be brought upon the stencilsheet to enable the same to be firmly and smoothly secured to the periphery of the duplicator drum. This operation may be more quickly and easil accomplished than is possible where the orward edge of the stencil-sheet is provided with closed slots. Moreover, it is unnecessary, as in the case. of the latter, to successively bring a slot and a button or stud into coaction, the few and simple movements described assuring coaction of all the buttons or studs and all of the recesses and notches as part of the same operation.

The reinforcing member (1, in addition to rotecting the stencil-sheet C against injury rom the roughened ed e of the forward portioncofthe backing-s set, also desirably strengthens the forward edge of the composite sheet at the ploint of contact with the pressure-roller of t e duplicator.

Having now described my invention, what I claim as new therein and desire to secure by Letters Patent is as follows 1. A composite stencil-sheet comprising a backing-sheet having a line of transverse perforations near one end, imperforate stencil and reinforcing sheets, secured to said backing-sheet between the end thereof and the ad acent perforations, said reinforcing sheet bein interposed between said backing and stenci -sheets and of a length sufiicient to extend a short distance over said line of perforations to form a cushion between the same and said stencil-sheet when said backing sheet has been torn off on said perforations, substantially as set forth.

2. A composite stencil-sheet comprising a backing-sheet having a line of transverse perforations near one end, a reinforcing sheet secured to said backing sheet between the said end thereof and the said perforations, and being of a length sufficient to eX- tend a short distance over said perforations, and a stencil sheet extending over said perforations and over said reinforcing sheet, the latter being adapted to form a cushion between said stencil-sheet and said perforations when said backing sheet has been torn off on said perforations, substantially as set forth.

This specification signed and witnessed this 29th day of October, 1913.

CHARLES FREDERICK GREEN.

' Witnesses:

O. J. WORTH, W. E. Rooms. 

